Keep object stores after conversations migrate to SQLCipher

js/background.js

@@ -131,10 +131,7 @@
     deleteAttachmentData,
     getCurrentVersion,
   } = window.Signal.Migrations;
-  const {
-    Migrations0DatabaseWithAttachmentData,
-    Migrations1DatabaseWithoutAttachmentData,
-  } = window.Signal.Migrations;
+  const { Migrations0DatabaseWithAttachmentData } = window.Signal.Migrations;
   const { Views } = window.Signal;
 
   // Implicitly used in `indexeddb-backbonejs-adapter`:
@@ -391,20 +388,6 @@
 
     Views.Initialization.setMessage(window.i18n('optimizingApplication'));
 
-    window.log.info('Running cleanup IndexedDB migrations...');
-    await Whisper.Database.close();
-
-    // Now we clean up IndexedDB database after extracting data from it
-    await Migrations1DatabaseWithoutAttachmentData.run({
-      Backbone,
-      logger: window.log,
-    });
-
-    const latestDBVersion = _.last(
-      Migrations1DatabaseWithoutAttachmentData.migrations
-    ).version;
-    Whisper.Database.migrations[0].version = latestDBVersion;
-
     window.log.info('Cleanup: starting...');
     const messagesForCleanup = await window.Signal.Data.getOutgoingWithoutExpiresAt(
       {
@@ -452,9 +435,6 @@
 
     Views.Initialization.setMessage(window.i18n('loading'));
 
-    // Note: We are not invoking the second set of IndexedDB migrations because it is
-    //   likely that any future migrations will simply extracting things from IndexedDB.
-
     idleDetector = new IdleDetector();
     let isMigrationWithIndexComplete = false;
     window.log.info(

js/modules/migrations/migrations_0_database_with_attachment_data.js

@@ -165,6 +165,17 @@ const migrations = [
       next();
     },
   },
+  {
+    version: 19,
+    migrate(transaction, next) {
+      window.log.info('Migration 19');
+
+      // Empty because we don't want to cause incompatibility with users who have already
+      //   run migration 19 when it was the object store removal.
+
+      next();
+    },
+  },
 ];
 
 const database = {

js/modules/migrations/migrations_1_database_without_attachment_data.js

@@ -6,12 +6,12 @@ const db = require('../database');
 const settings = require('../settings');
 const { runMigrations } = require('./run_migrations');
 
-// These are cleanup migrations, to be run after migration to SQLCipher
+// These are migrations for after the SQLCipher migration, currently not running
 exports.migrations = [
   {
-    version: 19,
+    version: 20,
     migrate(transaction, next) {
-      window.log.info('Migration 19');
+      window.log.info('Migration 20');
       window.log.info(
         'Removing messages, unprocessed, and conversations object stores'
       );